Coded coninuous inductive train control system



Aug. 3, 1943. P. w. SMITH CODED CONTINUOUS -NDUCTIVE TRAIN CONTROL SYSTEM Aug. 3, 1943. P. W. SMITH 2,326,049

CODED CONTINUOUS INDUCTIVE TRAIN CONTROL SYSTEM Filed Jan. 23, 1941 3 Sheets-Sheet 2 14 Am l'- i@ pl Emil?" FIGlB.

L2 (HE/FEM@ j 4 @HLFERFP 25 19 INVENTOR Vma MMM BY l 'VTO Caf Axe ATTORNEY Aug. 3, 1943. P. w. SMITH 2,326,049

CODED CONTINUOUS INDUCTIVE TRAIN CONTROL SYSTEM Filed Jan. 23, 1941 3 Sheets-Sheet Z l Fl 5.3.

INVENTOR BY Ww ATTORNEY it oscure Parenteel Aug; 3,1943

puree-een mmm; ies, 1941, sempre. meer genees. pamper) fever pilot 'contrai means. This 'leiter eeritmlmems een, merry Ceses, be employed te favairtageron locomotives in the interest lof eccmrn'fl steers consumption 'during the operation ofthe "loco- 55 felis fa very small expense;

-, puden@ rail @remercie ame 'f1-ral "treekway jappereitus an ear-carried apparatus,

reepetfively, "df ve enbrl 'system in 'aoco-rd- 4merce wither-representmveiitien. i

bers areV employed for the different parts at the,

various locations. a v l Considering thelocation Where `sections 2 3 meet, it can be Seen that, With east bound traic as indicated by the arrow il, `there is ajtrackflO relay TR. co-nnectedacross the entrance end oi each section land a track,V battery TB, connected acrossthe exit vend of each section. The track battery'is connected across'the rails in series with a usual'adjustable resist-anceV i". LIn-sefries with the battery and resistance is thesecondary of a .track transformer T and an 'adjustable inductance i.

block, of the character determined by the traffic conditions ahead. This control energy is inductively received by receiver coils REC carried by the vehicle ahead of the foremost pair of wheels and axle, and after passing thro-ugh Wires I3 and l d, pass through an amplilter i5 and a full- Wave rectifier Vl S to energize a 'code following relay CR. ThisY relay operates'its contacts i8 and I9 at the saine rate as the rate of the code being received. Relay CRis therefore deenergized when the vehicle in' question is in an occupied block, is vsteadily energized when in the block irnrnediately to the rear thereof, and vibrates its conneXt to the rear;

The primary winding of the tra-ck transformer is connected, through various contacts, so as to apply train control energyto' the track rails.

Dependentuponftraiic conditions .ahead this L.

energy fis eithercoded into separate current irnpulses ,applied at various ratesv or. the en rgywhich isalternating current preferably of non ,commerciali frequency 'su-ch, as 160 Ycycles per secondis steadilyappl-ied. `v: If coded, the energy Y is chopped into separate impulses-by mean-sof .a code motorv CM- controlled vby af code'contrcl relay CCR, which .in turn is energized upon the -entrance of a; vehicleinto section-due to the release ofv the track relay of vthe entered section,

all as-is obvious from the drawings.

j The character of train 4control Venergy to theftrack rails is determined by'trairiccoaditions'ahead by-rneansof the track relayflR of the locationinquestionZ a home distant relay HD .at'this location ivhichfis energized *Y through a Vfront point of the track relay of the `section next in'advance, and by a home distant-distant relay .if

HDD which is controlled by front points in series of rtlnejtracky relay ofthe block next-'in advance and ofthehome distant relay of the` block next 'in'V advance.- Thus,l at eachlocationithere is a track relay, a line relay which reects conditions oneblockvin advance, and a secondline relay whichreflectstraiic conditions two blocks inadvan-ce.l g

)Itwould appear that a detailed description of thetrackway control means is unnecessary andA likewise a'tracing of the various circuits involved appears unnecessary since the control is obvious from the drawings considered-in connection with the above description.

In brief, however, it can be said that, with Y Ythe vehicle Syoccupying track section 5, the track relay of ,this section is deenergized to thereby deenergize both ofthe line relays of the section to the rear.` Accordingly, inblock 5to the rear of the occupying vehicle, due to the wheels and axles of the vehicle lshunting the track circuit,

tacts at the rates of 75, 120, and 180 times per minute 'when in the three blocks, respectively,

Energized through Contact' finger i9 and front `point of relay CR is a slow release code following repeater relay CRFP, which remainsl attracted not only while relay CR is kin attracted position `but While relay CR is vibrating its contact linger l 9 at any of the different code rates.

YA relay 15B isy energized through Contact finger I9 and back pointvof relay CR, and contact ngcr v'2li and front point of relay CRFP, and hence, re-

lay 'I5R picks up and remains in attractedposition'sorlong as contact Vfinger i9 is vibrating at any of the coderates. Ivf this contact linger I3, however, V remains injra-ttracted,A vor retracted,

.position for any great length oftirnarelay '55E releases.l

v Contact finger i8 of relay CR energizes onehalf of therprinary winding of code transformer YC'I'When in attracted position with current nowing inone direction, and energizes' the other half 'of the primary of this transformer when in its retracted` position, with current flowing in the other direction, tvhereby to constitute a well vknown fpush-pull type of transformer Vto produce inthe secondary of this transformer current impulses atathe rate of the code then in Connectedacross the secondary of transformer CT is a circuit tuned to substantial resonance at 120 impulses per minute. This-circuit including a condenser 2| and the primary of a transformer 22, thesec ondary of Which is connected to the input sdeof a full-wave rectifier 23, the output side of which is connected across the winding of a code relay IZEBR.

In Ylike manner, a tuned circuit constituted by a condenser 24 and the primary of a transformer 25, is tuned to substantial resonance at 180 impulses per minute. The secondary of this transformer 25 is connected to the input side of a fullwave rectier 26,the output side of Which is conno train control energy is present in this block tothe rear ofthe occupying vehicle. immediately to the rear of the occupied block, is supplied with steadily applied alternating current. Block 3, to the rear thereof, is supplied With* alternating current coded at the rate of 'Z5 Yimpulses per minute, blockA 2,k next to the rear.

withacurrent coded at the rate of 12dy impulses per` minute, and block l, to the rear thereof and all blocksto the rear thereof, with current coded at the rate of 180 impulses per minute.

, Upon a vehicle, such as vehicle lo', entering a block, the coder is energized vto Vplace code across the rails at the exit endv of the entered Block i,

nected across the winding of a code relay lBR.

vRelays lt--lBRP and ISQRP are of the slow release type and these relays, as Well as relay 75B, are supplied with a short-circuited low-resistance copper band, or the like, to impart the ydesired slow release characteristics to these relays.' i

As thus far described, it can be seen that, with control energy coded at the rate of lil impulses .per minute received on the vehicle, relays 75B, and .CREP pick up and remain picked up. With energy coded at the rate of 120 impulses per minute being received, relay ISGR releases and relay 12GB. picks up and'rernainsup While 'ISR A,1r1dC1-3tFfP remain up. With energy coded at the rate of .V75 impulses per minute being received,

,both IESE and l'Rfrelease and stay down with TER and .'CRFP up. With steadily applied control energy received on the vehicle, code relay CR.

relay CRFP with the other relays 1ER, IZDR and 489B, down. Upon no control energy being re-V ceived relay CR releases and stays released and' all of the other above mentioned relays, including relay CRFP, remain in released position.

Employed in this systenr is a repeater relay [Z-INRP which repeats relay IBBR yand also relay NDR-and isenergized through circuits each includingv contact lnger Zland front point` of relay TSR and one including contactiinger 2B and front point of relay IZDR.y and the other contact finger 29 and front point of relay i803.

There is also a repeaterrelay IBIRP which repeats relay IBIIR and this relay is energized through a circuit including contact nger 2l and front point, Contact linger 29 and front point of relay 180B, and contact finger 28 and back point of relay HSR.

A plurality ci speed controlled contacts is einployed in the system and as indicated, these contacts are controlled by 'a speed controlled governor SG of the centrifugal type, driven from the car axle, for example. The speed controlled contact 3| is arranged to open when the speed exceeds 25 miles per hour, contact 32 opens at a speed above 40 miles per houncontactll opens at a speed above 60y miles per'hour, montaczt` 33a opens at a speed of 9D miles per hour, and contact 34 opens at a speed above Smiles perfhour. The speed contacts 3i, 32 and 33 are arranged 'in multiple with contact fingers 35,36 and 3l, re-

spectively,.of 'relays TSR, i20-l80RP,`and lRP while high speed contact 33a is 'between an indication suppression relay ISR and contact 33, Thus, ii a particular speed conta'ct3l`,` 3:2V or 33 be open, it is necessary that the corresponding multiple relay contact be closed, or else the indication suppressicnrelay ISR. which is energized through the speed contacts in 4series and the relay contacts in series, with thetwo sets of series contacts arranged in multiple, becomes deenergized. f Y

For example, if the speed of the vehicle .be above 6o miles per hounall oi the speed contacts except 33a are open, and unless contact 31 of. relay ISQRP be closed, relay ISRreleases. The other speed contacts Vand relay contacts` operate in like mannenwhereby, to prevent the release of the indicationsuppression relay ISR, the speed ci the vehicle must be kept within certain limits depending upontraiiic conditions ahead.

ceecl 6o miles per hour but, duev totcontacttta, not 9o miles per hour. If, however, the `code rate be lili), the limiting speedjis 60 miles per point of relay ISR; and contact linger 4l and back point of suppression relay" SupRQv/'hereby to apprise thejengineer that a-penaltywill be incurred unless prompt action be taken.

Should the engineer fail to take prompt action, a slow release penaltyrelay PR, which is energized through contact .finger #Zand front point Vof relay ISR, releases after a shorttim'e, such as, 'for example, two andorre-half secondsfto therelf the code in force be the 1180 code',the speed can ex-` by deenergize a brake applying valve EPV which is normally energized through contact linger d3 and front point of relay PR. Upon valve EPV becoming deenergized, an automatic emergency brake application is incurred which cannot be released until the vehicle is brought to aspeed as low as 5 miles per hourywhe'reupon speed Contact 34 closes to reenergize'relay PR through an obvious circuit whereby to reenergize valve Assume, however, that the engineer is alert and upon seeing the energized suppressive brake in dication SBI, that he vappli-es his brakes to produce a manual service brake application. performing this act the Vsuppression relaySupl?, is energized in .the manner, for example, as disclosed in PatentNo. 2,223,131, referred to above. Thisv relay remains energized so long as 'the brakes are applied, and if the braking is`icontinued soas `togconstitute a full service ,brake application, this relay remains energized even though the brake valve handle should be rc- Aturned to release position. Upon suppression lay SupR. picking up, the suppression brake indi cation is removed and if the braking beefiected l since the deenergizaticn oi the valve EPV is tion, since the release of relay CRF? door prevented. Y

In' this system, upon a vehicle entering an occupied block, where no control energy is re ceived, relay CRF? rel-easesV whereby to deencn gize and cause to sound a whistle valve AWV which is normally energized (and silent) through contact ringer and iront'point` ci relay CRF?. This apprises the engineer that he is in a danger lock and4 unless he takes prompt action he will incur the penalty of an emergency brake aoolica- =g1zes penalty relay PR,` which normally receives its energy through contact finger 43 and iront point,

vof relay CRFP; If the engineer take no suitable order to release the brakes and proceed, as en hour. If the code rate be 75,the limiting speed is 4G miles per hour. Ifthe control energy be of a push button, whereby to complete a plained above. Y

Upon hearing the whistle which, it should be noted, is 'arranged to sound when' dcenergized, the engineer Vshould depress his acknowledging contacter AclcC which preferably is in the form k-up circuitior an acknovvledgingl stick relay AS is energized through acknowledging conta-ot i andVback-point. Upon the picking up ci relay AS .this `relay 'sticks upV independently of the acknowledging contact through a circuit'including contact.ringer 48 and back point, and contact Contact 5l in thefenergizing circuit `for the penalty relayR whereby,yii the acknowledging contacter is tied down, or held down, undue time, or otherwise misused, the penalty `of an automatic emergency brake. application islin-V curred.l Y

After acknowledgment, and the release 'of the acknowledging contactor, the penalty relay is energized through a circuit'including acknowledging oontact i and front point, Contact linger 52 andiront point of -relay AS,v and contact l2 and front point of relay ISR.. Thus the vehicle can proceed but vonly at a speed not above miles per hour, since if it exceeds this speed,` relay ISR becomes deenergized and the braking penalty is incurred.

Upon train control energy beingY received, whether it be coded or steady, relay CRFP picks up to vthereby deenergize stick relay AS, and

thusplace the system under the control of the various speed contacts, as described above.

. The various speed limits set up as described above are accompanied by cab signal indications corresponding tothe various speed limits. As shown in the drawings, whenV the control energy is coded at the 180 rate, relay ISDRP is in attracted position, and the cab signal G is ener-` gized through a circuit including contact nger i 53 and front'point of relay lSRP.

Yand back point, contact finger 51B and back point,

contact finger 55 and back point, contact nger it and back point, of relay AS, and contact nger 5lV and front point of relay CREP'.l Upon the train entering an occupied block, where no control energy is received acknowledgment must be performed to prevent the braking penalty, and hence the acknowledging stick relay AS is picked up while relay CRFP releases, and the cab signal R is rst energized through contact finger 58 and back point of relay CRFP, etc., and after the acknowledging stick relay is picked up, through a multiple branch including contactnger 53 and front point of relay AS. Y ,i

In connection with the above system there is a dial D haVng sraduations indicating speed of the vehicle in miles per hour, and yaspeed hand SH, which is controlled by the speed governor- SG, and at all-times indicates the speed of the vehicle. The various cab signal indication means G, etc., are arranged around this dial oppo'site the limiting speeds which uthe particular indications are associated with, whereby the engineer has before him a visual interpretation,

of the cab signal indication in terms of speed in miles per hour.

Also, arranged adjacent therdial, as shown in which it controls. For example, should the code ratebe 120 per minute, the cab signal G/Y is in force, and the limiting speed which is 60 miles per hour, is clearly indicated `to the engineerAon the associated dial, While the actual speed of the vehicle, as indicated by the pointer is constantly before him. Thus, the. operation of the vehicle with the system of the type described above, is greatly Afacilitated by the arrangement of the parts as described just above.`

Also, includedinthis system, is a means for recording the speedA of the vehicle, and this is constituted by amarking member which marks the speed of the vehiclelin miles per hour on a tape GS which is traveled at a uniform rate of speed by a clock work B1 connected to turn the spool or drum 68 to thus make a speed-time curve 69 on the tape.

An acknowledging recording relay ARR is provided which is energized'upon each acknowledging act through a circuit including acknowledging contact .lil and back point. Upon each acknowledging act, relay ARR is energized to attract its armature'l and cause a marking member 'i2 to make a mark on tape B to indicate the then speed of the vehicle, these acknowledging marks being indicated at 73. Thus, after a locomotive run, this record tape will show the vehicle speed throughout the run, and the speeds at which the vehicle entered occupied blocks, and thus furnish very valuable information for guidance in future operation of the locomotive.

AIn Fig. 2 is shown the receiving casing for the train control system described above, and this casing, which is essentially a unitary compact housing, has the speed and acknowledging recorder positioned in a portion at the top, and is identied by the word recorden Below the re corder is a section carrying the dial D with the cab signals arranged around the dial, and opposite the limiting speeds for each signal indication. Below the dial portion of the casing is a portion which receives the speed governor, the relays, etc., and which is equipped at the bottom with an inlet portion I4, receiving the governor drive.` At the right of this lower portion of the casing is a portion identied as speed control contacts, in which the various speed controlled contacts, described above, can be conveniently housed. The various wires involved in the system can be led into theunitary housing in the form of a conduit 15.

Thus, as :viewed in "f'l'g, 2, a compact housing is provided for receiving allof the'various parts of the above described train control system with the speed governo-r controlling not only lthe speed contacts which set up speed limits but also controlling a speed indicating hand SI-I. This hand cooperates with' a dial graduated in miles per hour, and has adjacent the dial the cab indicationapositioned to give visual knowledge at all times of the significance of the various cab signals. This same governor also controls the speed recording device. There is assurance with the acknowledging -contactor and the suppressive brake indication means, also mounted on the casing adjacent Vthe speed dial, that the engineer will retain all or" the various indication means of the system constantly in view and thus there is a greatly added assurance that more than usual vigilance will be exercised by the engineer in his operation of the locomotive.

' VIn Fig. 3 is shown a slightly modified form of the invention wherein means is provided for making a recordA of the particular signal aspect under which the vengine is proceeding throughout its entire run. The record tape 55 is shown together with its speed timecurve 59 and its acknowledging records 13'. j

Y For recordingk the signal aspect under which. the engine is running, each signal light such as `three markers Sil, di and 9.2L`

` system.

acaso@ G has. connectedV in multiple with it a recorder operator, as G Rec, as byy wirer8il. Thisgreen recorder G Rec can; be any `usual; tractive type of relay having an armaturerlgpivoted atgZ and carrying` a stylusv or marking device lwhicn is normally biased-by gravity: outfci contactftyiththe` record tape l'butvrhich is pressed-incontacttherewith upon its actuating magnet beging energized. The systcin-isrepresented` asoperatr, ing :under proceed conditions'wherein signaLlamp G is energized and the greenirecordert G Rec; isf

energized;` In these circmnstancesfthe stylus 831'fis pressed against therecord tape (i6 andgis producing the horizontal lineyld which records i the fact that the engine is running under a greenn cab'signal.

Inca similar manner, signal lamp G/Y has/connected in multiple with Vit arecorder: opera-torl In like manner, signallamps, ii/G, and Ra ave connectedzin multiple therewith bythe; Wirest Rccyenergized' through a4 circuit including;` .wireito operatelitsstylus;

, apluralaspect calo signal, control rneanstor the el, t8 and i9 the'recorder operatorsi Y/G Rec;

Y Rec and R Rec'. tors are, respectively; arranged These threev recorder opera- Thus it appears thata record tape is produced inaccordance with this invention,zduiing the run ofi a locomotive which hears a timespeedcurv'e.;

a record ci each operation of the 'acliiiovvledging'AY contacter, and arecord thronghoutthe runof jest what signal aspectsfwere in force andfor` what duration during the ,Y j j i As referred to above, ifY ittedesiredjto;equip` a locomotive having a speedcontrolled'system` oi train control of the typey disclosed above, with control system suchasr is` generally known; as

Vthe loco-valve pilotf system,` it.` is azvery simple matter to s o equip'thc locoinotive.` All that: is;V necessary is to supply a secondindication hand on the dial D, and control itby a valvepilot so.- as4 to indicate on the dial in terms of milesper'hdur the position of steam valve cut-oil?` whichl` islmost;

economical at the various locomotive speeds.; ilt I is further necessary merely to. record thetindicai- A to operate l the forreceiving and responding distinctively to.

' said energies, a -centrifuge, contacts controlledf yley the-centrifuge and cooperatingwiththe vehicle tion of this valve cut-oilY position on-the existing,

tape te which is already present intheusys'tem for the purpose of recording the speedij'time, curveil. il f" i i Thus, a system is provided which assures;

greater -acility in operation `of a locomotive, and; Y greater assurance in safety in operation, andlendsf itself very readily and econornicallyito expansion, to include other control means such, asmthat; enerally known as the loco-valve piloti control` The above rather speciiic description` ci' the,` present invention has been' given solely by vvay` of illustration, and is `not intended, in, any inanner whatsoever, ma limiting sense. Itis to be; understood that various. modications adapta.-

tions and alterations may be appliedtol meet the vrequirements of practice Without, any .manner departing :from the spirit or scope of the invention except as limitedby the appended claims.

What I claim is; l. In a train control system, vehicle carried means for receiving and responding to train control energy conditions on the trackway of characteristics differing in accordance with different trafc conditions ahead, `rneans on the vehicle for establishing the same speed limit in response Vto each of two of said different energy conditions, a plural aspect calo signal, and control means' for the signal distinctively'responsive to said I 'n a train, 4means for receiving and respending.-toY train. con#V i trot energy conditions on thetraclrwayot char-iv tions', and Va speed indicating point Vconnected to the centrifuge andinoaable Aover energy conditions te cause ,the signal to l.display a diierentfaspect for cachot said diierc-nt energy conditions.` 'Y A control systenr, 'vehiclej carried acteristics @litteringin accordance-With difierent.

tra-dic conditions ahead, means on the vehiclefor' estahlishing the saine speed limit in response to each of tvtcaoi said 'different energycorfiditions.,v

signal distinctively responsi4 etto said lencrgycon-y ditions toyc'ause, the signal-to display a diierent aspectfor eachofsaid diijlerent energy conditions, a normallyinoperativey penalty device, and

means for making theldevice operative upon the vehicle exceeding an established speed` lin-lit.`

3. Inga Atrain control system, vehicle carried. means foi-'receiving and responding tojtrain. control; energy conditions onV thetrackWayf of characteristics diilering-` in accordance with trafic conditions ahead, means on the vehicle for estab.- lishing the saine speedlimit in response. to. each.k of two of said diierent conditions,- a-plural aspect 4calo signal, control' means for the signal distiific.-A tively responsive to said conditions to. cause, the signal to display a different` aspect -for each` of said' diierent conditions a` normally inoperative penalty device,` means for making the device operativegupon the vehicle exceeding `an estais.-` lished speed limit, means-for making the, penalty deviceopera-tive uponthe display of one of said signalaspectsyinanually operative acknowledging.

n1eans,. andV circuit means efectiveupon the operation of theacknowledging means toy prevent the penalty device trom-becoming operative in responseto said display otsaid oneo said signal` aspects. 1 p

4'. In agtrain. con-trol system; combination with means for placingcontrol` energy on the Wayside coded diierently in accordance. Withtraiiic conditions ahead, vehicle carried means means` to'.A establishtdiierent,'speed limits in re-` sponse to the diierently kcoded energiesreceived,

a normally inactive penalty means made active Kupon4 anestahlished speed limit Vbeing exceeded,

-aplural aspect cabsigna-l, `signal meansftiiojr displaying different signal aspects et cliierent..reev strictivenesses in response tothed-irerently coded energies received, a- 'dial' bearing speed graduae-r 'operatively the dial to indicate vehicle speed,y the`` various signal aspects beingl positioned adjacent. the. dial different restrictivenesses in response to the diiierently coded energies received, a dial bearing speed graduations, a speed indicating pointei` operatively connected.v to the speed responsive device and movable yoi'fer'tliefdial to indicate vehicle speed, the various signal aspects being positioned 'adjacent the dial and opposite the' graduation denoting the limi-tof speed permitted underits corresponding signal aspect, a normally inoperative penalty device, means making' the device operative vuponV an established speed limit being exceeded unless manually prevented-sup'- lpression means operable to prevent'operatic'm of said device, and a warning signal displayed'upo'n exceeding an established speediimitandposi-V tionedfadjacent saidldial.V

k6; in a train control system, with means for producingV different control energy conditionsv on rthe wayside in Vaccordance with traine conditions ahead; vehicle carried means for distinctivelyY respondingr to said energy conditions, a speed responsive device, contacts controlledv by the device and co-operatingwith the V`vehicle carried means for establishing different speed limits in response to the diferent energy conditions,Y a plural aspect `cab signal,l means for displaying diierent Y diierentrestrictivenesses in response to the different energy conditions, a dialV bearing speed signalV as ects Yoi means controlled Y.by said speed device to recordthe vehicle speed; and means to mark on the with means for producing different control `energy conditions Von the wayside in accordance with trailic conditions ahead,l vehicle carried. means for receivingand responding distinctively" to said'energy conditions, a speedl responsive' device, contacts'controlled bythe device-and co-V v operating with said vehicle carried' moans for' in combination.

speed rrecord each operation or the acknowledg-r 7V. 'In atrain control system, in con'obinationv establishing diiierentsp'eed limits in response to' the" different energy conditions, a plural aspect cab signal; means-for displaying different signale.

aspects of different-restrictivenesses inl response tothe diierent energy conditions, a dial bearing speed graduations, aspecd indicat ng pointer operatively/connected to the speed deviceand the various signal aspects being positioned adjacent the dial and opposite the 'graduation denoting the limit of speed permitted under its corresponding signal aspect, a normally inoperative penalty device', means for making the device operative upon an existing speed limit being exceeded unless it bemanually prevented, manually operable suppression means operable to pre- 65 Y movable over the dial tofindicate vehicleispee l said one signal aspect, means controlled by said speed devceto record the vehiclespced,l and means' tomark on the speed record each operation of the acknowledging means.

'8. Ina train controlsystem, in combination with'imeans for placing control energy on the` wayside coded diierently in accordance with tramo conditionsahead, vehicle carried means for receiving and distinctively responding to said energy, a plural aspect cab signal, circuit means connecting the vehicle carried means to the signal forY oontrollingithe signal so as to display o 5. different signal aspectsfof different restrictiveness in response to the differently coded energies received, a Vrecord tape, means for moving the tape atfa substantially uniform rate, a signal recording means foreach signal aspect and each operative for marking distinctively on the tape 1 of the signal.

9..In a train control system, in combination withv means for producing different control energy conditions on the wayside in accordance with trafc conditions` ahead, vehicle Vcarried means for distinctively responding to said conditions, a centrifuge, contacts controlled by the centrifuge and co operatin. T V with the vehicle carried means for establishing different speed limits in response tothe said different conditions, a plural aspect cab signal, means controlling the signal for displaying'a different signal aspect of different restrictivenesses in response to the said diierent conditions, a dial bearing speed grad nations; a speed indicating pointer operatively connectedto the centrifuge and movable over 4the dial to indicate vehicle speed, the various trolled by said centrifuge to reco-rd the vehicle speed, means tolmark on the speed recordeach operation of the acknowledging means, a signalrecorder for each aspect of the signal, and effec tive when energized to mark on the speedrecord, and circuit means foi-.selectively energizing the signal recorders to `agree atiall times with the energia/ation of the cab signal.

Pianoro: w. SMITH. 

